A: Yes! The addendum for the Jumanji Fluxx rules also includes these instructions about playing without Dangers:

Playing Without Dangers: Some players (new players in particular) may prefer playing without the Dangers. In this case, simply set aside:

• all of the Danger cards
• the Meta Rule: No More Lives
• the Action: The Sound of Drums

The Mystery Fluxx rulesheet does not include how to play without Dangers, but if you wanted to do so, these are the cards you would leave out:

• all the Dangers
• the Meta Rule: The Final Act
• the Surprise: That Wasn’t Me!

Note that there could still be elimination due to the Time Bomb. Instructions for how elimination works, and when the eliminated player can jump back in, are included in the Dangers section of the rulesheet.